Economics is a mathematical model, so we must firmly believe that only with a good mathematical foundation can we do finance. Those who study international trade must have studied various models of Keynes and the principle of diminishing returns to scale in management economics or econometrics. These principles are obtained through the calculus principle of mathematics, and your study is called advanced mathematics. On this basis, ricardian model of ITC and others is also based on mathematical tools, and I can completely deduce it now by looking at ricardian model.
Let's start with linear algebra. You will often use linear methods such as regression analysis (such as DEA method and linear regression analysis) to study advanced economic theory or analyze data in the future. If you don't understand linear algebra, how can you understand the profound meaning behind the economic conclusion? Generally speaking, just like a small vendor, the first thing he needs to know is what money is, and he can add and subtract. .
If you just think that the study of international trade theory is useless. When the time comes, it will be another matter to take an endorsement as a customs broker and mix with an international trade enterprise manager.